The film follows a small group of commandos sent to Greece on a seemingly impossible mission: to blow up massive Nazi guns that are capable of destroying passing Allied ships. The mission is led by Mallory (Gregory Peck), who forms a disparate international team of commandos that includes Andrea (Anthony Quinn), a Greek who harbours against Mallory a personal grudge so intense that he has threatened to kill Mallory after completion of the mission; Pappadimos (James Darren), a hot-tempered Greek determined to exact revenge on the Germans for their brutal occupation of his homeland; Miller (David Niven), a British explosives expert; and Brown (Stanley Baker), a British engineer and knife fighter. Also aiding the men are two resistance fighters, Maria (Irene Papas) and Anna (Gia Scala). The team is beset by a number of obstacles, including the discovery of a traitor in their midst, before they finally gain access to the Nazi guns. In a race against time, the group attempts to sabotage the weapons before they can wreak havoc on a passing Allied fleet.

The original director of The Guns of Navarone, Alexander Mackendrick, was fired, and various actors were considered—notably William Holden, Marlon Brando, Cary Grant, and Gary Cooper—before the final cast was assembled. Despite such initial uncertainties, a gripping adventure story emerged, directed by J. Lee Thompson and featuring an edge-of-the-seat finale. Dimitri Tiomkin’s score was also notable. The film spawned a star-studded but inferior sequel, Force 10 from Navarone (1978).